fix(skills): make weather workflow Windows-safe

tests/agent/test_builtin_weather_skill.py

@@ -0,0 +1,14 @@
+from nanobot.agent.skills import BUILTIN_SKILLS_DIR
+
+
+def test_weather_skill_uses_windows_safe_single_today_request() -> None:
+    content = (BUILTIN_SKILLS_DIR / "weather" / "SKILL.md").read_text(encoding="utf-8")
+    normalized = " ".join(content.split())
+
+    assert "On Windows PowerShell, use `curl.exe`" in normalized
+    assert "bare `curl` may resolve to `Invoke-WebRequest`" in normalized
+    assert "https://wttr.in/London?1&m" in content
+    assert (
+        "Do not fetch current conditions separately when a today or forecast "
+        "request already includes them."
+    ) in normalized